Re: [Geotools-gt2-users] building gt2 with maven

[James M. <j.m...@ge...>]

At 11:04 20/11/2002, you wrote:
>Hi folks,
>
>I just cvs'd a copy of all of the source and tried to build with maven.
>There were lots of errors? My understanding of maven is that it should
>go and get dependancies if necessary and it should build correctly.
>
>What did I do wrong?

Hard to say without knowing what some of the errors were, could you paste 
some of them in a message.

The following is a general discussion of the maven build system, it would 
be good if everyone on this list tried the system out as it is hopefully 
set to become the main build method soon.

First, grab a recent copy of the GT2 source code, you can do this via CVS 
or by downloading the latest source snapshot from:
http://geotools.sf.net/daily/lib/gt2-src-snapshot.tar.gz

You will need the latest copy of maven, I am using beta-7 which you can 
download from:
http://www.ibiblio.org/maven/maven/distributions/
Installation is straight forward, basicaly you need to unpack the archive 
and place the /bin folder on your path and set an environment variable 
'MAVEN_HOME' to point to the folder which contains the bin folder.


Maven uses a few files to manage the build process, these are:
project.xml - contains information about the project and dependencies
project.properties or build.properties - special options which control 
aspects of the build
maven.xml - optional extra scripts for performing special tasks.

Each module in geotools2 is treated as a project in its own right, so in 
each geotools-src/modulename folder you will find a project.xml file that 
contains the details specific to that module.

However, as the modules also have a lot in common you will find a master 
project.xml file in the geotools2 directory that they all extend.

If you want to do a complete build of all working modules then put yourself 
in the geotools2 directory (the one that contains geotools-src) and type 
'maven'

The first time you run maven it will grab a lot of files that it needs for 
itself, then it will try to download the files it needs to build GT2.  It 
will try ibilo and geotools.org for these files and it will generate error 
messages when it fails to find them at ibilo before trying geotools.org.

It will work out what order to build the modules in itself and then try to 
process them in that order.  As it finishes each module it will 'install' 
the finished jar into a repository (MAVEN_HOME/repository).  The following 
modules will then build against the file in the repository if they depend 
upon it.

Because of this, if a module fails to build, say filter, then a module 
which depends on filter will show an error like this:
Unable to download filter-0.1.jar

This is misleading as it should not be attempting to download filter-0.1 
instead this means that filter failed to build and install itself into the 
repository.

All being well, the final line of the build output should give you a list 
of which modules built without error and were installed.

To get more information about the status of each module and any test errors 
you can run
maven site
from the geotools2 directory, this is a lengthy process so we have a server 
which is doing this for us on a regular basis, you can find the output at
http://modules.geotools.org

If you want to build an individual module without doing a complete build 
(which can take a while) then go into the specific module directory and type
maven
you can build javadocs with
maven javadoc
and run the unit tests with
maven test
generate a site just for the module with
maven site
and find out a list of other things you can do with
maven -g

All output will go in a 'target' folder

NOTE: If you change a module that other modules depend on make sure you do a
maven jar:install
So that an updated copy is placed in the repository.

Give maven a try and feedback your experiences,  our aim is to make the 
build process as painless as possible.

All the best

James



-- 
James Macgill
Center for Computational Geography http://www.ccg.leeds.ac.uk
Spell Checker (c) Creative Spelling inc (aka my dyslexic brain)
http://www.geotools.org a client side java mapping toolkit.